During the recent U.S. election period, our team heard your concerns and feedback regarding political ads appearing on publisher sites. As a Product Manager who helps build the AdSense product, I'd like to take a moment to explain our ad targeting technology and policies, and what we're working on to offer you even more controls.

Ad Targeting

I wanted to help clarify first how advertisers are able to target your sites. As you know, ads that appear on AdSense sites are provided by advertisers participating in the AdWords program. To help publishers earn revenue, advertisers are able to target ads not only based on the content of a site, but also based on the audience of the site. When we first started AdSense in 2003, we only offered contextually-targeted ads; advertisers bid on keywords, and our system matched those keywords to the content of publishers' pages. As we developed the product, we expanded these targeting capabilities. For instance, placement targeting allows advertisers to select specific topics, sites, and pages on which they want their ads to run. In the U.S., our placement targeting tool also allows advertisers to find sites serving a specific audience, such as "Males ages 18-24."

To help new and existing publishers better understand our targeting options, our support teams will be reviewing and expanding the material available on our Help Center and homepage to make sure it better communicates our offerings. In addition, we'll be exploring different methods of explaining this information, such as through webinars and videos, and demonstrating how publishers can optimize their sites to take advantage of these targeting options.

Advertising Policies

We also received questions about why political ads are able to run on Google and AdSense sites. The Google advertising program is managed by a set of editorial policies that we have developed based on various factors, including user and customer experience. While Google or its executives and employees may express opinions about specific political issues and candidates, Google's advertising system does not favor one political position over another. Our network provides advertisers with a way to reach their audience, whether they are companies selling products or political campaigns promoting candidates or issues. Just as Google's advertising system does not favor one car manufacturer's ads over a competitor's in our auction, we also allow ads regardless of the particular political position they represent.

Publisher Ad Control

As we've expanded to new forms of advertiser targeting, we've also added controls for the ads that can appear on your sites. Our automated targeting technology will never understand your users as well as you, so it's important that you have the ability to control their ad experience. For example, we mentioned earlier this week that tools such as the Competitive Ad Filter and Ad Review Center are designed for you to prevent specific ads from appearing on your pages.

We've heard your feedback about how quickly filters take effect and the ability to block specific categories of ads, and we're working hard to improve our current controls and provide more powerful ones in the near future. Over the next couple weeks, we plan to improve the speed of your filters, and we're working towards filters in the future that will take effect in less than an hour. We'll also continue improving the Ad Review Center, giving you ways to block entire categories of ads in addition to individual ads. We are also working on ways for you to establish guidelines for the type of ads that will be acceptable to your users, so you can "set it and forget it," while feeling comfortable that users will have a good ad experience.

One of our goals with AdSense is to help you easily generate revenue for your site without much work, so that you have more time to focus on developing great content. Many of our best ideas, like the Ad Review Center, are inspired by your feedback and suggestions. Please keep letting us know how we can make AdSense a better product.